In the left-hand lane, there was a 40-year-old New Jersey detective with his wife and three children buckled into the family’s Kia minivan. They were setting out for a long drive home at sunset on a warm Saturday night.

In the right-hand lane, there was another middle-aged man, a Marylander who friends say had just purchased his first home. He was pulling onto the road from a busy Wawa gas station, on a stretch of tidy homes and shopping plazas in suburban Anne Arundel County. He had stopped with a friend to get a cold drink.

But as the two vehicles began making a left-hand turn toward the highway, there was a swerve, then another, according to an account in court papers. Tempers flared. The officer purportedly brandished a pistol. The two men pulled over.

Just a mile and a minute after it all began, the Maryland man lay fatally wounded on the side of the road and the New Jersey detective was headed for jail.

In this June 8 photo provided by the Maryland State Police, Hudson County (N.J.) police Detective Joseph Lamont Walker is shown in a booking image. (AP)

Joseph Lamont Walker, 40, of Eastampton, N.J., was ordered held on $1 million bond Monday by an Anne Arundel District Court judge. He remained in custody on charges of second-degree murder and manslaughter in the death of Halethorpe resident Joseph Dale Harvey Jr., 36.

Police said Walker fired a gun twice during the roadside encounter. The first shot struck Harvey in the thigh, they said. Seconds later, a second shot fatally wounded Harvey.

But exactly how the altercation began, and how it escalated so quickly, remained in dispute Monday. So, too, did details of the critical seconds after both men got out of their cars.

An attorney for Walker on Monday said Harvey had threatened the officer’s family, according to CapitalGazette.com. A passenger in Harvey’s car, however, said that his friend had tried to protect himself after the first shot was fired and that several seconds passed before the deadly shot.

Patrick McAndrew, an attorney for Walker, characterized his client as a victim in interviews Monday. He told CapitalGazette.com that Walker, a detective with the Hudson County Prosecutor’s Office, just outside Manhattan, had identified himself as a police officer and warned Harvey to stop.

There was no answer Monday at Harvey’s small white house in Halethorpe, a modest neighborhood where the sound of jets could be heard overhead descending toward nearby Baltimore-Washington International Marshall Airport.

One of Harvey’s friends, Adam Pidel, the passenger in Harvey’s car Saturday night, featured prominently in a Maryland State Police report describing the minutes before the deadly altercation.

Pidel told police that Harvey had just pulled out of a Wawa gas station near the intersection with Route 175 and Route 3. Just beyond the gas station, both lanes are allowed to make a swooping left onto Route 3, to head toward Baltimore.

Harvey’s car was in the right-hand lane. Walker’s van was beside it in the left-hand lane. As the two began to turn, Walker’s van suddenly cut in front of Harvey’s car, Pidel said.

“Harvey got angry and used the shoulder to avoid being struck and then continued driving on the shoulder,” according to the report.

As the two vehicles progressed north on Route 3, each swerved repeatedly, “nearly striking each other several times as each intentionally swerved at each other,” the report said.

“Pidel stated at one point, the driver, Mr. Walker, pointed a gun at him and Harvey,” the report said.

About a mile from where the altercation began, and just before merging onto Interstate 97, Walker pulled over onto the shoulder, authorities said.

Harvey pulled over a short time later and began walking back toward Walker’s van, according to the police account. Pidel said he stayed behind and saw Walker get out of his van as Harvey walked toward it, then briefly get back inside and come out with a pistol.

A passing motorist reported seeing Harvey approach the officer in an “aggressive manner.”

The passing motorist also appeared to witness the first shot, reportedly seeing Harvey grab his shorts and lift up his leg.

Pidel told police that he ducked for cover. About four seconds passed, Pidel said, and then he heard more shots.

About that time, another passing motorist saw Harvey fall to the ground.

The police report did not attempt to unravel what happened in between. Only Walker and Pidel called 911, according to the police report. Investigators listened to the recordings “and they conflict each other,” it stated.

Maryland State Police recovered two .45-caliber shell casings from the scene, according to the report, which concluded that Walker “did feloniously, without malice or aforethought, kill and slay Joseph Dale Harvey.”

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